My experience is that nothing is more durable than having more spokes, even if the rim is deeper. The difference from 36 spokes to 32 is more than anyone expects, and the difference from 32 to 28 or 24 is absurd. For your particular case, however, it probably will not make much difference in practice. The problem is that while the deep V may be more likely to stay round, it will be about the same or less tough laterally, depending on the shape differences of the rim walls. I'd say it's a toss-up.